This application is based on Patent Application No. 2000-403208 filed Dec. 28, 2000 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a contact pin module used for testing an electronic circuit in an object to be tested having the internal electronic circuit and a testing device provided with the same.
2. Description of the Related Art
Semiconductor integrated circuits mounted to an electronic equipment or others are subjected to various tests at a stage prior to being actually mounted so that latent defects therein are removed. These tests are carried out in a nondestructive manner by the application of voltage stress and the operation and reservation at a high temperature corresponding to a thermal and mechanical environmental tests. Among these tests, there is a burn-in test effective for removing initial-inoperable integrated circuits, in which the operational test is carried out for a predetermined time under a high temperature condition.
An inspection jig used for the burn-in test is generally referred to as an IC socket, for example, disclosed in Japanese Patent Application Laid-open No. 10-275667 (1998), comprising a printed circuit board (a printed board) having an input/output section through which a predetermined test voltage is supplied to and an abnormality-detection signal representing a short-circuit or others is returned from an object to be tested, a object under test accommodating member (a socket body) having an accommodation section for mounting a semiconductor element (semiconductor integrated circuits), for example, of a BGA (ball grid array) type to be tested, a cover member (a lid) having a pressing section (a pressure plate) in contact with an upper surface of the semiconductor element and pressing the same at a predetermined pressure, for covering an upper part of the object under test accommodating member, and a hook member rotational moveable held by the cover member and engaged with the object under test accommodating member to fix the cover member to the object under test accommodating member.
The object under test accommodating member is provided with a contact pin module which is a collectivity of contact pins for electrically connecting terminals of the semiconductor element with electrodes of the printed circuit board. Such a contact pin module is formed of a plurality of lead frames superposed with each other, each lead frame being formed of contact pins electrically connected to the respective terminals of the semiconductor element and contact pins electrically connected to the respective electrodes of the printed circuit board, which contact pins are continuously arranged in the same plane while confronting each other.
For example, as shown in FIG. 14, a contact pin module 2 includes a semiconductor element 6 mounted to a socket body (not shown) as an object to be tested, a plurality of lead frames 4 electrically interconnected to a printed board 8 for inputting/outputting a test signal relative to the semiconductor element 6, and an upper frame member 12 and a lower frame member 10 in association with each other for accommodating the plurality of lead frames 4.
In this regard, FIG. 14 illustrates only one lead frame 4 in two or more lead frames 4 superposed with each other, and eliminates the other of them.
The lead frame 4 consists of a plurality of contact pins 4Ci (i=1 to n wherein n is an integer) formed at a predetermined interval in the same plane. The numbers of the lead frames 4 and the contact pins 4Ci are selected, for example, in accordance with the arrangement and the number of terminals of the semiconductor element 6.
The contact pin 4Ci consists of a object under test-side end portion 4A to be guided in a movable manner into an aperture 12b of the upper frame member 12 and coming in contact with the terminal of the semiconductor element 6, a printed board-side end portion 4B to be guided into an aperture 10b of the lower frame member 10 and coming in contact with an electrode pad of the printed board 8, and a curved connecting portion 4D connecting the object under test end portion 4A to the printed board end portion 4B.
According to this structure, when the semiconductor element 6 is pressed toward the contact pins 4Ci-side with the above-mentioned pressing section, the object under test-side end portion 4A moves through a predetermined distance against the elastic force of the connecting portion 4D. Thus, due to the elastic force corresponding to the deflection of the connecting portion 4D, the object under test-side end portion 4A and the printed board-side end portion 4B of the contact pin 4Ci are brought into contact and thereby electrically connected with the terminal of the semiconductor element 6 and the electrode pad of the printed board 8, respectively, with substantially the same contacting force.
As another embodiment different from the curved contact pin 4Ci formed in one piece, a contact pin 14 shown in FIG. 15 may include a object under test-side contact member 18 to be in contact with a terminal of the semiconductor element 6, a printed board-side contact member 22 to be in contact with an electrode pad of the printed board 8, a spring member 20 disposed between one end of the object under test-side contact member 18 and one end of the printed board-side contact member 22 to transmit a bias corresponding to the displacement of the object under test-side contact member 18 to the printed board-side contact member 22, and a casing member 16 for accommodating the spring member 20, the end of the object under test-side contact member 18 and the end of the printed board-side contact member 22.
Also in the above contact pin 14, the other ends of the object under test-side contact member 18 and the printed board-side contact member 22 are brought into contact with the terminal of the semiconductor element 6 and the electrode pad of the printed board 8, respectively, with substantially the same contacting force. At that time, if a proper contacting force at the object under test-side contact member (end portion) and that at the printed board-side contact member (end portion) are different from each other, the above-mentioned bias of the contact pin is selected to be an intermediate value between the proper contacting forces at the object under test-side contact member (end portion) and that at the printed board-side contact member (end portion) since the bias of the contact pin is a single bias.
For obtaining the secure electrical connection at the object under test-side contact member (end portion) and the printed board-side contact member (end portion) of the contact pin between different objectives, however, it is necessary for each end of the contact pin to come in contact with the objectives to be connected electrically according to proper contacting force of the object under test-side contact member (end portion) and the printed board-side contact member (end portion) rather than contacting forces such an intermediate value.
In view of the above problems, an object of the present invention is to provide a contact pin module used for the test of an electronic circuit in an object to be tested having the same and a testing device provided with the contact pin module, capable of individually adjusting contacting forces with a terminal of the object to be tested and with an electrode of a printed circuit board having a signal input/output section.
In accordance with the present invention which is proposed to attain the above object, there is provided contact pin module comprises a first connecting section formed of an elastic conductor and having a terminal portion electrically connected to a connecting terminal of an object to be tested including an electronic circuit, a second connecting portion consecutive to the first connecting portion and formed of an elastic conductor to be integral with the first connecting portion, the second connecting portion having a terminal portion electrically connected to an electrode of a board connected to a signal input/output section through which a test signal for the object to be tested is input and output, a supporting member disposed at an approximately intermediate position between the first and second connecting sections and supporting the conductor so that a contacting force of the terminal section of the first connecting section to the connecting terminal and a contacting force of the terminal portion of the second connecting portion to the electrode are individually adjustable, and a holding member for holding a plurality of the first connecting portions, the second connecting portions and the supporting members in a overlaid manner.
Also, the contact pin module according to the present invention comprises a first connecting portion having terminal portions formed of elastic conductor electrically connected to a plurality of connecting terminals, respectively, of an object to be tested and including electronic circuits therein, a second connecting portion having terminal portions formed of an elastic conductor consecutive to the first connecting portion and electrically connected to a plurality of electrodes, respectively, of a board connected to a signal input/output section for inputting and outputting a test signal for the object to be tested, a supporting member disposed at an intermediate position between the first and second connecting portions and supporting the conductor so that a contacting force of the terminal portion of the first connecting portion to the connecting terminal and a contacting force of the terminal portion of the second connecting portion to the electrode are individually adjustable, and a holding member for holding a plurality of the first connecting portions, the second connecting portions and the supporting members in a superposed manner.
Further, the contact pin module according to the present invention, wherein the conductor in the first and second connecting portions may comprise curved portions consecutive to the terminals portions, respectively, or radii of curvature in the first and second connecting portions may be approximately equal to each other.
The testing device according to the present invention comprises a contact pin module as defined in claim 1 or 2, an object under test accommodating member for positioning the contact pin module relative to a connecting portion of the contact pin module in a signal input/output portion and a connecting terminal of an object to be tested, the signal input/output section supplying a test signal to an object to be tested including an electronic circuit therein and delivering an output signal from the object to be tested via the contact pin module, and the object under test accommodating member for accommodating the contact pin module and the object to be tested thereinto, and a pressing mechanism for pressing the object to be tested placed on the contact pin module relative to the contact pin module.
As apparent from the above description, contact pin module and the testing device provided with the same according to the present invention since the supporting member is disposed at an approximately intermediate position between the first and second connecting portions and supporting the conductor to be capable of individually adjusting a contacting force of the terminal portion of the first connecting portion with the connecting terminal and a contacting force of the terminal portion of the second connecting portion with the electrode, it is possible to individually adjust the contacting force with the terminal of the object to be tested and that with the electrode of the printed circuit board having the signal input/output section, for example, by suitably selecting shapes of the first and second connecting portions.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.